In recent years, advances in technology, as well as ever-evolving tastes in style, have led to substantial changes in the design of automobiles. One of the changes involves the complexity of the electrical systems within automobiles, particularly alternative fuel (or propulsion) vehicles that utilize voltage supplies, such as hybrid and battery electric vehicles. Such alternative fuel vehicles typically use one or more electric motors, often powered by batteries perhaps in combination with another actuator to drive the wheels.
Such vehicles often use two separate voltage sources, such as a battery and a fuel cell, to power the electric motors that drive the wheels. Power electronics (or power electronics systems), such as direct current-to-direct current (DC/DC) converters, are typically used to manage and transfer the power from the two voltage sources. Also, due to the fact that alternative fuel automobiles typically include direct current (DC) power supplies, direct current-to-alternating current (DC/AC) inverters (or power inverters) are also provided to convert the DC power to alternating current (AC) power.
To date, most automotive propulsion systems have utilized three-phase systems. However, higher phase number (e.g., five-phase) systems have recently been developed which may provide lower torque ripple, improved power and torque, increased fault tolerance over lower phase number (e.g., three-phase) systems. As the power demands on the electrical systems in alternative fuel vehicles continue to increase, there is an ever-increasing need to maximize the electrical efficiency of such systems. There is also a constant desire to reduce the size of the components within the electrical systems in order to minimize the overall cost and weight of the vehicles.
Accordingly, it is desirable to provide improved methods and systems for operating an electric motor, particularly high-phase number electric motors for use in automotive electrical systems. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.